Hidden mechanics

Rules confirmed by reading the game’s code. The game doesn’t spell these out.

Each building can be triggered 10 times per week

Every building starts the week with 10 triggers. Each time it reacts to a trigger it uses one, and at 0 it ignores triggers until the next week. Treasuries also skip buildings that are out of triggers. A few buildings have their own limit instead: Enclave, Factory, Grain Silo, Graveyard, Lodging House, Mason, Statue and Wizard’s Tower.

Treasury chains stop after one hop

A Treasury triggers when a building within 7 tiles earns Gold, then activates a random adjacent building. Gold earned by a building that a Treasury activated is tagged as coming from the Treasury and does not trigger Treasuries again. A building between them that activates neighbours breaks the tag, so the chain can continue up to the trigger limit.

Some heirlooms don’t stack

Ingots only checks whether one copy is equipped, so extra copies do nothing. Coin Stack does stack: every copy adds its own Gold.

Score limit

The game stores score as a 64-bit whole number, so the largest score it can hold is 9,223,372,036,854,775,807. Very long endless runs can reach it, and in the release build scores past it wrap around to a large negative number.